With the development of wireless communication technology, people have higher and higher requirements on the wireless communication. MIMO technology can significantly improve channel capacity. Applying multiple antennas both to transmitting terminal and receiving terminal can significantly improve spectrum efficiency and transmission efficiency. Generally, people measure noise power of MIMO antennas by spectrum analyzer (SA), however, the SA can only measure the noise power of a single antenna subjected to its single signal port. In order to measure MIMO antennas noise power, the SA needs to increase peripheral circuits such as amplifier, switch and so on. This not only leads to high complexity, but also brings in external noise which will negatively influence the measuring. To conveniently obtain more precise measurements, a new type of MIMO antenna noise power measuring method and apparatus are needed.